Electrical phonograph pick-up



March 28, 1933. s. ARUBEN 1,902,900

ELECTRICAL PHONOGRAPH PICK-UP Filed 001'.. 24, 1950 Patented Mar. 28, 1933 i UNITED STATES PATENT OFFICEy SAMUEL RUBEN, OF NEW ROCHELLE, NEW YORK ELECTRICAL PHON OGRAPH PICK-UP Application led October 24, 1930. Serial No. 490,903.

This invention relates to an electrical is -an increase of current flow through the phonograph pick-up device for translating oXide. mechanically recorded acoustic vibrations The contact between the opposing electrode into electrical undulations. An object of surfaces must be uninterrupted throughout 5 the invention is the provision of a device for the various pressure changes produced by the 55 elfectiiigsucli translation with minimum disl'llOVemelit of the stylus; this is secured by tortion and With an efficiency above that of damping by the use of any suitable retlie device of the vprior art. This invention silientl material such as rubber; it also preconstitutes an improvement upon that devente excessive movement of the stylus. For

l scribed in my United States Letters Patent maximum eiiicicncy and minimum distortion 60 Number 1,757,547. the push-pull or twovphase electrical arrange- Broadly, my invention consists of a device ment is best adapted to this device. a for translating mechanically recorded acous- F01 2L beitel' Undls'lldlng 0f the lIWGIltlOll tic vibrations into electrical impulses of coriefelfell@ iS mde t0 the eCCOmpanying draw- 1 responding frequencies, through changes in 111g illustrating one embodiment thereof in G5 the resistance of a vanadium pentoxide elec- WhlCh F lgs-1,2 and 3 represent different views trode in response to pressure changes pro- Ot the device, Figs. 4 and 5 showing sectional duced by the movement 0f t Stylus vihmtviews thereof. Referring more particularly ing through its Contact with the surface to the drawing, at l is an insulating base upon 20 undulations upon a moving body, the undu- Whloh metal Support Q s mounted- A@ 3 70 lations representing mechanically recorded 1S a needle 0r .SYIUS I'lgldly mounted in a acoustic vibrations. I have found that fused rotatable lltlmu'lum mmbe? 3a, hYlIlg L vanadium pentoxide has pressure electrical Shaft 3b Which is mounted in 'a bearing in resistance characteristics somewhat similar Support 2 havmg a rubber lining at 4. To

2 t0 those of Cuprous Oxide- It is these Chiu.- further damp the rotatable member a rub-'75 acteristics that are employed to effect the bel' blanket 4a 1S Placed Wound it particu translation of recorded sound vibrations into 1Mb between that mmbl and the Valuable electrical oscillations. For translation with TQS/mmm@ butto@ 9 here @O mPOSed 0f .thin minimum distortion the vibratory electrode layers 0f Vmadum Petoxlde, upon llckel is controlled by a resilient body as a means bases 9a Which are held in position by screws 80 of dampiiig7 the vibrations, and is in sur- 9b' ,Screws 9b 3F@ 100km by SCYGWS 9c- C911* face Contact with a Vanadium pentoxide G1ec tacting With resistance buttons 9 is conductive mode. In this device one of the electrodes plate 5, mounted upon the aluminum member constitutes a stylus, one end of Which is in 3&2 Outside of ,rubber blmket i-'L The Stylusy Contact with the record7 the other electrode 3, is connected in an electricalcircuit by means 35 being a pentoxide layer upon each of tWo 0f @Crew 6 lead? and termuml 8' The V?" members in surface contact with the vibrator-'y nadlum Penufxm? buttons are comected 1n electrode. Or the vanadium pentoXide laynneleucal Clrllt bfmml'gdof terminals 10' l 40 ers may befupon opposite sides of the vibran le Open lon O me Wwe lts total l n Y resistance is initially the combined contact 90 rnoigrlLASE? and crystal internal resistance of vanadium t `d in response to the movement of its pointed peiivifdaim is:

end in contact with the recorded undula 1 A phonograph pickup Comprising avi- 45 tions, the Pressure Pon the Wmadlum Pent" bratory stylus and a pressure sensitive elec- 95 OXdG WINGS, thi? CUIT 611i? HOW therethlOugh trode composed of vanadium pentoxide, said changing accordingly. With increased pieS- electrode constituting a part of an electrical sure upon the vanadium pentoXide electrode, circuit and said stylus being adapted to vary due to the negative lcontact resistance cothe pressure on said electrode in accordance 50 etlicient of this material with pressure, there With mechanically recorded vibrations to 100 ktrode in surface contact with the other electrode, one of'said electrodes being composed of vanadium pentoXide, and means for damping the movement of the stylus.

4:. A device for translating mechanically recorded vibrations into electrical undulations, comprising a base supporting a rotatably mounted stylus constituting an electrode, a vanadium pentoXide electrode held in surface contact with the other electrode by a resilient body. f

5. A device for translating mechanically recorded vibrations into electrical undulations, comprising a base supporting a rotatably mounted stylus constituting an electrode, a layer of vanadium pentoXide upon a nickel base, constituting another electrode and means for maintaining said electrodes in surface contact, said means comprising a resilient body.

6. A device for translating mechanically recorded vibrations into electrical undulations comprising a base support, a stylus constituting a vibratory electrode, a cooperating electrode having a plurality of members, each member being in surface contact with said stylus', one surface of each pair of said surfaces in contact being composed of vanadium pentoXide.k

`7. AA device for translating mechanically `recorded vibrations into electrical undulationsV comprising a base support, a stylus constituting a vibratory electrode, means for damping the movement of the stylus, said means comprising a resilient body, a cooperatingelectrode having a plurality of Contact members, each in surface contact with said stylus, one surface of each pair of said surfaces in contact being composedl of vanadium pentoxide. l

8; In a phonograph pick-up, a stylus constituting a vibratory electrode, and a coopern ating electrode having two contact members mounted in surface contact with the vibratory electrode, two of said. electrodecontacting areas vbeing composed of vanadium pentxide. Y

9. In a phonograph pick-up a stylus constituting a vibratory electrode, means for damping the movement of the stylus, comprising ak resilient bodyand a cooperating directioncauses an increased contacting re-` sistance of the vanadium pentoxide at one of said electrode contact areas and a decreased contact resistance atthe otherlectrode contacting area. c v Y Y l1. In a phonographfpick-up, a stylus constituting a vibratory electrode, vmeans fory damping the movement of the stylus, said means comprising a resilient body, and a cooperating electrode having two contact niembers in surface contact with the rvibratory electrode, two of the electrode contacting areas being composed of vanadiumlpentoxide, the vibratory electrode being so mounted that the movement of the contact area ofV the vibratory electrode in one direction causes an increased 4Contact resistance ofthe vanadium pentoXide at vone of said electrode contacting areas and a decreasedcontact resistance at the other electrode contacting area.

12. In an electrical phonograph pick-up a pressure sensitive electrode composedV ofV vanadium pentoXide and mea-ns actuated-by the undulations ofthe acoustic track of' mechanically recorded vibrations to vary the pressure on'said electrode. Y

13. A Aphonograph pick-up comprising a vibratory stylus and a pair of electrodes in pressure contact .with each other, one of saidI yelectrodes being composed'of vanadiumpentoXide and said vibratory stylus being adapt- ,ed to vary the pressure between said electrodes to translate mechanicallyrecorded vibrations into electrical undulations in an electrical circuit including said-electrodes.V

14e. A. device for translating mechanicall-yA` recorded vibrations into electrical undulations comprising a base, avpair of fixed spaced apart pressure sensitive electrodes mounted on said base,said electrodes being composed of a material, the contact resistance of which varies with the pressure applied, a vstylus mount pivotally mounted on said. basel between said electrodes, a head forming a part of said stylus mount, a metallic bridging electrode mounted on said heady of saidstylus'v mount substantiallyconforming in shape to a portion of said head and being in pressure contact with said pressure sensitive electrodes, a rubber blanket interposed between said head of saidy stylus mount andsaid me- 

